Omega-3 polyunsaturated fatty acids and reduction of depressive symptoms in older adults: A systematic review and meta-analysis

Baia Z-G, Bo A, Wu SJ, Gai Q-W, Iris Chi I (2018) Journal of Affective Disorders 2018 Dec, 241: 241-248 doi.org/10.1016/j.jad.2018.07.057

Web URL: Read the article on Science Direct here

Abstract:

Highlights

•: This review suggested the efficacy of n-3 PUFA treatment with dosage greater than 1.5 g/d in reducing depressive symptoms among adults aged 60 or older.
•: We searched ten databases and gray literature. Nine studies with low risk of bias were included.
•: This review synthesized the effects of n-3 PUFAs on depressive symptoms among older adults and explored subgroup differences based on participant characteristics and intervention characteristics.
•: This review used robust variance estimation in meta-regression to synthesize treatment effect size estimates and conduct moderator analyses.

Abstract

Objective

The aim of this study is to systematically review the efficacy of omega-3 polyunsaturated fatty acid (n-3 PUFA) supplements in reducing depressive symptoms among older adults aged 60 and above.

Methods

Relevant electronic databases were searched from their inception to June 4, 2018, including Medline, Embase, Web of Science, Cochrane Library, PsycINFO, Global Health, CINAHL, ClinicalTrials.gov and Chinese Biomedical Medicine Database. Two reviewers independently screened for eligible studies, extracted data, and assessed risk of bias of the included studies. The effect size data were analyzed using robust variance estimation in meta-regression.

Results

Nine studies were included. The overall treatment effects of n-3 PUFA supplements in reducing depressive symptoms for older adults was not statistically significant (d = −0.202, 95% CI = −0.463, 0.060). Meta-regression found interventions with dosage of n-3 PUFA greater than 1.5 g/d had an average effect size of −0.428, with a 95% confidence interval of [−0.822, −0.035], which is statistically significant. Meta-regression did not find significant moderating effects of comorbidity, baseline depression, intervention duration, and EPA–DHA ratio, potentially due to limited statistical power.

Limitations

The current review only included 9 studies based on literature search in major English and Chinese databases, which provided limited statistical power for moderator analysis and the results are suggestive only.

Conclusions

The meta-analysis of 9 RCTs found mixed findings of the efficacy of n-3 PUFA in the treatment of depressive symptoms among older adults aged 60 and above. More high-quality, large-scale RCTs are needed to confirm the current conclusions.

FAB RESEARCH COMMENT:

See the associated news article:

Omega-3 Polyunsaturated Fatty Acids May Reduce Depressive Symptoms in Older Adults

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